摘要 |
A computer implemented method provides a plurality of audio data files 26, each comprising a header 30 and audio signal data 28, and configures a database by providing a plurality of associations, each indicating an association between a respective one of the plurality of data files and an index data value to enable the data file to be indexed in the database, wherein the index data value has a dependence upon frequency content of the audio signal. In some cases the frequency content of the audio signal comprises a plurality of frequency data windows. The processor 20 applies a transform such as a Fourier transform to each data window (100, 110 fig. 2) to determine spectral or frequency content (100â , 110â fig. 2) and writes the spectral content data to a second memory area 18 of memory 14. The index may be based on a centre of gravity of a weighted average of frequency content. |